What is an integrated circuit?
Since its inception in the 60s of the twentieth century, integrated circuits (IC) have had a huge development and are widely used. Computers, quartz watches, electronic clocks, washing machines, game machines, TV remote controls, and many home appliances come with one piece or several integrated circuits. In the computer, no need to say. The rapid improvement of the feature of the computer is due to the continuous development of integrated circuits.
Before integrated circuits appeared, electrical circuits used each component such as a resistor, capacitor, bipolar lamp, triode lamp, etc. Separately, solder them to a pre-printed circuit board or use separate wires to solder the components together. When the number of components is too large, such as a circuit with 100 thousand transistors, its volume will be extremely large, and power consumption is also very large. Moreover, the circuit is very prone to failure. Any loose weld or a component failure can affect an entire circuit. Later, people took advantage of advanced scientific and technical measures, manipulated the necessary components in the circuit into a small semiconductor piece. All of the above difficulties have been solved. That is an electronic integrated circuit, referred to as an integrated circuit. Of course, these components must be extremely small and have to use very thin wires to connect those very small components.
How to assemble so many electronic components onto a small semiconductor silicon plate? Over decades of research and development, it now has a relatively complete technical process, i.e., integrated circuit machining technology. That includes oxidation, light etching (photolithography), doping, metalization, and so on. That process must be repeated many times. Fabricating an integrated circuit typically takes several tens or even hundreds of stages.
To classify integrated circuits with different accumulation levels, it is generally referred to as a circuit consisting of 10 to 100 transistors (transistors) as small-sized integrated circuits (SSI); call a circuit consisting of 100 to 1000 transistors as a medium-sized integrated circuit (MSI). Call a circuit consisting of 1000 to 10000 transistors is a large-sized integrated circuit (LSI). A circuit consisting of 1000000 transistors or more is a super large integrated circuit (VLSI). We can know that the so-called size means only more or less the number of transistors in a piece of the integrated circuit. However, the integrated circuit volume does not increase in proportion to the size of its “size,” but rather tends to be smaller and smaller. Of course, that also means increasing component accumulation density.